Proposals have been made, in particular, for means for manual locking of the aforementioned bascule, which are capable of immobilizing the latter in a stable position corresponding to the release of the boot upper, as disclosed in FR-A 2 648 327. According to the latter, the manual locking means are constituted by a piece which is movable in vertical translational motion at the upper end of an arm of the bascule and which can be manually operated in an upward sliding movement, in order to extend this upper end of the bascule and to cooperate with a notch provided in the upper part of a recess in the upper, so as to hold the bascule in the released position. Downward slide control of this mobile piece frees the latter from the upper notch and allows it to pivot under the action of an elastic device, to ensure that the lower end of this bascule is stopped, on the aforementioned stop set on the rear part of the shell base, for an operative position.
To allow operation of the mobile piece in translational motion in either direction, this piece has a projecting part forming an outer gripping element, without which any control would be impossible.
These locking means have a number of disadvantages, since it is necessary to provide, first, a relatively thick bascule, since the latter supports the mobile part and the gripping element attached to it, and second, an upper notch to be cut in the upper.
Finally, as regards use, this system still involves two operations to produce a stable release of the boot upper, i.e., a substantially rectilinear thrusting movement perpendicular to the upper, in order to cause the bascule to pivot in a movement freeing its lower end from the stop, and a thrusting movement, also rectilinear and substantially parallel to the upper, so as to engage the mobile component beneath the upper notch.
This last disadvantage does not inhere in other conventional devices for immobilization of the upper of a boot, in which the means for locking, and indeed for control, of the bascule are independent from the latter. As an example, in the ski boot described in the French Patent Application FR 2 619 317, the upper-immobilization device comprises a stop means which is subjected to the continuous action generated by an elastic force which pushes it into its closed position, and can be maneuvered into an open position in opposition to this force, by means of a control device located in the upper.
As illustrated, the stop means is housed in a recess in the upper and is shaped like a dual-arm lever pivoting around a pin mounted in the upper, while the control device is mounted so as to pivot on the outside of the upper and in proximity to the end of one of the arms of the stop lever.
In this kind of construction, the upper is released by virtue of an outward swivelling movement of the control mechanism which, by exerting pressure on the corresponding arm of the stop lever, produces the release of this arm from its stop on the shell base. To relock the upper in the skiing position, it then becomes necessary to bring the control device back against the upper in order to permit the stop lever, subjected to the elastic return force, to be placed in the engaged position in relation to its stop on the shell base.
This immobilization device has the disadvantage of protruding in a very pronounced fashion on the rear part of the upper, and of requiring voluntary manipulation of the control mechanism in order to return to a locked position of the upper for the purpose of skiing.
As a further example, mention may be made of the device for immobilization of a ski boot upper described in German Utility Model GM of Utility Gm 80 20 898 which shows an immobilization device incorporating a lever attached to the upper and capable of being stopped on an element of the boot shell. The lever is controlled by an outer traveller that can be moved linearly and can affect angularly the position of the lever beginning at an end, or central, point of articulation.
As in the preceding case, this device has the disadvantage of protruding from the rear part of the upper in permanent and variable fashion, since the traveller can be moved in translational motion. Furthermore, it always requires a voluntary operation performed by the skier to move from the released position to the locked skiing position. In addition, the momentary-release maneuver, with the potential for automatic relocking, is not possible.